1. Field of the Invention
The present invention relates to a reverberator, used for an electronic musical instrument or an accompaniment music playing apparatus, that adds reverberation to an input sound signal.
2. Description of the Related Art
A conventional reverberator, when mounted on an electronic musical instrument or a karaoke apparatus (an apparatus for playing recorded music to accompany a singer), adds reverberations to an input sound signal to improve musical tones in a high tone range, to provide increased depth and body for output musical tones and to induce a desirable aural sensation, such as a romantic, dreamlike effect.
Well known are such reverberators as mechanical reverberators and digital reverberators. Mechanical reverberators employ an oscillation characteristic of a metal plate or a coil spring member to add reverberation to an input tone signal, while digital reverberators combine multiple tone signals that have different delay times to obtain a like result.
With the prior art reverberators, however, resonance occurs when an input tone signal, to which reverberation is added, is a pure tone, which is an overtone that is represented by a sine wave. A resonance phenomenon that occurs, i.e., a so-called flutter echo, prevents the production of a preferable reverberation characteristic.